1. FIELD OF THE INVENTION
The present invention relates to washing machines.
2. DESCRIPTION OF THE PRIOR ART.
There have been proposed washing machines comprising an unperforated washing drum, rotatable in either direction of rotation, and a conveyor screw which is firmly connected to the drum and subdivides the latter into individual treatment zones with at least one principal washing zone. The chambers are distributed along the periphery of the washing drum in the area of the principal washing zone and in communication with the internal space of the washing drum. A heating device, for example a heating coil, is situated in each of these chambers, and heats the liquid present in these chambers, the liquid heated in this manner being mixed with the liquid present in the lower portion of the washing drum during the rotary displacement of the washing drum in the one direction or the other, and thus resulting in an increase in the temperature of the liquid available for the washing operation and thereby in an intensification of the washing operation.
The incorporation of several chambers arranged along the periphery of the washing drum in the area of the principal washing zone is necessary, because at least one chamber -- namely the chamber situated at the lowest position at the instantaneous position of the washing drum -- must be filled by the liquid in each position of the washing drum, this liquid then being heated by the heating device and mixed with the liquid present in the washing drum. The other chambers are free of liquid in this case, so that the heating devices associated with those other chambers must be rendered inoperative.
The great structural complexity consequent upon the incorporation of several chambers with corresponding heating devices and piping systems, is disadvantageous. This structural complexity leads not only to high production costs and in bulky appearance, but also renders such a washing machine liable to breakdowns.
It is an object of the invention to overcome the above disadvantages.